This update is housecleaning some older entries (not happy with their quality, so have to bring them up to snuff), and also a few new supplements. This week we have supplements that range from highly effective to little-evidence to even dangerous!
Tribulus terrestris, the world's most popular herbal T-booster, got an interesting update. Now, it would actually be incorrect to say that tribulus never increases testosterone, since one study in infertile men noted a very small increase, but even then, tribulus severely underperforms and it is still not a practical intervention for testosterone. Despite that, there is some promise for cardioprotection and it appears to actually be a potent antioxidant in organs (exceeding the potency of vitamin E in some preclinical data). It can still, however, only be recommended for libido enhancement as all other info is preliminary.
Secondly is Anacyclus Pyrethrum, which is a testosterone boosting aphrodisiac from Ayurvedic medicine. Not much can be said about this compound aside from it being an alkylamide source (similar to maca or Spilanthes Acmella) and suggesting that the entire molecular class of alkylamides are interesting for male sexuality. Anyways, there is not enough evidence to recommend this herb for anything.
The updates of past herbs in our database, tribulus and anacyclus, expanded upon the herbs but did not yield any new therapeutic usage of these herbs. Both are still faith buys with insufficient evidence to recommend for any real usage beyond a possible libido enhancement
For the new herbs, starting from the most promising to the least:
Peppermint (oil) has been added to the database, and it has also been added to the stack for irritable bowel syndrome. In short, peppermint oil is a potent muscle relaxant that is thought to have poor absorption (thus only relaxing the stomach, throat, and intestines) and reliably and effectively reduces abdominal pain in persons with IBS. It should reduce abdominal pain in all persons actually, and this may be the only symptom it beneficially influences.
Tinospora cordifolia (Guduchi) is an ayurvedic immune booster, and while it has limited human evidence, it appears to be very potent in reducing symptoms of allergic rhinitis (nasal allergies) with a 'strong' rating and potency comparable to spirulina. It shows beneficial effects on many other parameters (depression, diabetes, androgen-like effects, etc.) but these are either underpowered relative to other herbs or under-researched as a whole. By far, the most interesting effects are the anti-allergic properties and the potent stimulation and protection of macrophage functions (supporting the idea that it is immunosupportive).
Centella asiatica (Gotu Kola) has been added on request. Oddly, this herb appears to be recommended as interchangeable with bacopa monnieri for cognition yet has no research in humans on that (and thus it cannot yet be recommended for cognition). It appears to be most well-known for wound regeneration, which is a claim that shows plausibility and benefits in rats yet does not have good human evidence for, and appears to be quite promising for heart health in regards to chronic venous insufficiency (similar to pycnogenol and horse chestnut). Overall, centella asiatica might be an interesting supplement if you want to support venous circulation (varicose veins in particular) yet there is some reason to use if over the aforementioned two supplements, perhaps to try out the wound regeneration or cognitive enhancement bits.
Now on to the lackluster updates; Angelica Gigas is a Korean traditional medicine that is recommended for women's health. It is known to increase estrogen in rats, and in vitro is a potent anti-androgen; its immunosupportive effects may be pretty much negated by itself (different molecules in the plant act against each other), and there is no human evidence overall. If anything, this would be something to keep an eye out for in hopes that it gets more research in menopausal women.
And finally, the dangerous. Acorus calamus contains a molecule known as beta-asarone which is a surprisingly potent stimulator of GABAA neurotransmission and may have cognitive enhancing properties, it also appears neuroprotective and anti-epileptic. Why isn't this recommended? Well, doses lower than the active dose (i.e. if you supplement this herb you will be subject to the following) over a prolonged period of time induce intestinal tumors. This plant has literally been deemed unfit for human consumption, and as such the buy links on this page have been revoked.